Mercedes-Benz C300
29 MPG The 2026 Mercedes-Benz C300 is EPA-rated at 29 MPG combined (25 city / 35 highway). Over 15,000 miles a year that is about 517 gallons, $1655 a year in fuel, or $0.110 per mile at $3.20/gal.
Across its full 2008–2026 run it averages 26.4 MPG, improving by 8 MPG over 16 model years.
Running cost at different fuel prices and mileages
The figure everyone actually wants, and the one the EPA does not publish — because it depends on a fuel price no agency will commit to.
| Fuel price | Per mile | 10,000 mi/yr | 15,000 mi/yr | 20,000 mi/yr |
|---|---|---|---|---|
| $2.50/gal | $0.086 | $862 | $1293 | $1724 |
| $3.00/gal | $0.103 | $1034 | $1552 | $2069 |
| $3.20/gal | $0.110 | $1103 | $1655 | $2207 |
| $3.50/gal | $0.121 | $1207 | $1810 | $2414 |
| $4.00/gal | $0.138 | $1379 | $2069 | $2759 |
| $4.50/gal | $0.155 | $1552 | $2328 | $3103 |
| $5.00/gal | $0.172 | $1724 | $2586 | $3448 |
Every model year
| Year | Combined | City | Highway | EPA fuel cost/yr | CO₂ g/mi | Trims |
|---|---|---|---|---|---|---|
| 2026 | 29 MPG | 25 | 35 | $2650 | 307 | 1 |
| 2025 | 29 MPG | 25 | 35 | $2650 | 303 | 1 |
| 2024 | 30 MPG | 26 | 36 | $2550 | 300 | 1 |
| 2023 | 29 MPG | 25 | 36 | $2650 | 308 | 1 |
| 2022 | 29 MPG | 25 | 35 | $2650 | 305 | 1 |
| 2021 | 27 MPG | 23 | 35 | $2850 | 324 | 1 |
| 2020 | 28 MPG | 24 | 35 | $2750 | 315 | 1 |
| 2019 | 27 MPG | 23 | 34 | $2850 | 330 | 1 |
| 2018 | 27 MPG | 24 | 33 | $2850 | 324 | 1 |
| 2017 | 28 MPG | 24 | 34 | $2750 | 319 | 1 |
| 2016 | 28 MPG | 25 | 34 | $2750 | 315 | 1 |
| 2015 | 28 MPG | 25 | 33 | $2750 | 318 | 1 |
| 2011 | 20.7 MPG | 18 | 25 | $3717 | 430 | 3 |
| 2010 | 21 MPG | 18 | 26 | $3650 | 423 | 3 |
| 2009 | 21 MPG | 18 | 25 | $3650 | 423 | 1 |
| 2008 | 21 MPG | 18 | 25.5 | $3650 | 423 | 2 |
Where a model year offered several engines or drivetrains, the figure is the average across all EPA-tested trims that year — the trim count is shown so you can see how much averaging is involved.
How it compares in its class
Among the 227 compact cars models tracked here, the Mercedes-Benz C300 ranks 43 on current figures, against a class average of 26.6 MPG.
Closest more-efficient alternatives in the same class: Chevrolet Prizm (29.3), Ford Focus FWD FFV (29.3), Hyundai Veloster (29.3), Audi A4 (30), BMW 330i (30).
Tailpipe CO₂ is rated at 307 grams per mile, which works out to roughly 4.6 tonnes a year at 15,000 miles.
Questions
What MPG does the Mercedes-Benz C300 get?
The 2026 Mercedes-Benz C300 is rated at 29 MPG combined by the EPA — 25 city and 35 highway. Across all 16 model years in the database it averages 26.4 MPG, ranging from 20 to 30 depending on year and trim.
How much does a Mercedes-Benz C300 cost in fuel per year?
At 29 MPG and 15,000 miles a year, it burns about 517 gallons — roughly $1655 a year with fuel at $3.20 a gallon, or $0.110 per mile. The EPA's own published annual figure for the 2026 model is $2650.
Has the Mercedes-Benz C300 become more efficient over time?
Yes. It has gone from 21 MPG in 2008 to 29 in 2026 — an improvement of 8 MPG, or 38% across 16 model years.
Is the Mercedes-Benz C300 efficient for its class?
It ranks 43 of 227 in the Compact Cars class on current figures, against a class average of 26.6 MPG. That is 2.4 better than typical for the class.
EPA test figures from fueleconomy.gov. Cost per mile and annual fuel spend are computed at a reference price of $3.20 per gallon — use your own price. Estimates based on official test figures and average fuel prices. Real-world consumption varies with driving style, load, terrain and maintenance.